The steamer Virginius was on the 26th day of September, 1870, duly registered at the port of New York as a part of the commercial marine of the United States. On the 4th of October, 1870, having received the certificate of her register in the usual legal form, she sailed from the port of New York and has not since been within the territorial jurisdiction of the United States. On the 31st day of October last, while sailing under the flag of the United States on the high seas, she was forcibly seized by the Spanish gunboat Tornado, and was carried into the port of Santiago de Cuba, where fifty-three of her passengers and crew were inhumanly, and, so far at least as relates to those who were citizens of the United States, without due process of law, put to death. It is a well-established principle, asserted by the United States from the beginning of their national independence, recognized by Great Britain and other maritime powers, and stated by the Senate in a resolution passed unanimously on the 16th of June, 1858, that--American vessels on the high seas in time of peace, bearing the American flag, remain under the jurisdiction of the country to which they belong, and therefore any visitation, molestation, or detention of such vessel by force, or by the exhibition of force, on the part of a foreign power is in derogation of the sovereignty of the United States. In accordance with this principle, the restoration of the Virginius and the surrender of the survivors of her passengers and crew, and a due reparation to the flag, and the punishment of the authorities who had been guilty of the illegal acts of violence, were demanded. The Spanish Government has recognized the justice of the demand, and has arranged for the immediate delivery of the vessel, and for the surrender of the survivors of the passengers and crew, and for a salute to the flag, and for proceedings looking to the punishment of those who may be proved to have been guilty of illegal acts of violence toward citizens of the United States, and also toward indemnifying those who may be shown to be entitled to indemnity. A copy of a protocol of a conference between the Secretary of State and the Spanish minister, in which the terms of this arrangement were agreed to, is transmitted herewith. The correspondence on this subject with the legation of the United States in Madrid was conducted in cipher and by cable, and needs the verification of the actual text of the correspondence. It has seemed to me to be due to the importance of the case not to submit this correspondence until the accurate text can be received by mail. It is expected shortly, and will be submitted when received.